Field of the Invention
The present invention relates to a face-up-type Group III nitride semiconductor light-emitting device whose light extraction performance is improved by providing a reflective film in an insulating film.
Background Art
Patent documents 1 and 2 disclose a flip-chip-type Group III nitride semiconductor light-emitting device in which a reflective film is provided in an insulating film. In such a light-emitting device, migration of a metal forming the reflective film is prevented through electrical insulation of the film by enclosing the film with the insulating film.
Patent Document 1: Japanese Patent Application Laid-Open (kokai) No. H11-340514
Patent Document 2: Japanese Patent Application Laid-Open (kokai) No. 2005-302747
The Group III nitride semiconductor light-emitting device having a structure disclosed in Patent Document 1 or 2 is of a flip-chip type. Conceivably, application of such a structure to a face-up-type device could improve the light extraction performance of the device. Specifically, the light extraction performance could be improved by providing a structure in which a reflective film enclosed with an insulating film is formed below an n-electrode and a p-electrode (i.e., on the side of a sapphire substrate), so that light emitted toward the n-electrode and the p-electrode is reflected by the reflective film, to thereby inhibit absorption of light by the n-electrode and the p-electrode.
The present inventors have conducted studies on a face-up-type Group III nitride semiconductor light-emitting device having the aforementioned structure. However, the present inventors have found that the light-emitting device exhibits insufficiently improved light extraction performance, since light reflected by the reflective film is absorbed by a light-emitting layer, or light reflected by a resin for sealing the device is absorbed by a wiring portion of the n-electrode or the p-electrode.